Ultra Scarce 1940s Glenn Colorule for Testing Color Vision dansk international Beginning in the 1950s

Beginning in the 1950s

rown glazed shoe

Craven (there is some debate about it from what I've read

which stains and etches easily

Ultra Scarce 1940s Glenn Colorule for Testing Color Vision dansk international Beginning in the 1950sI have found a bunch of academic papers and studies discussing the use of the Glenn Colorule, but can't find even a picture of another out there anywhere. There are records of in a few academic libraries, so I know it was produced by s explained on the box text, it was made to be used to test the color vision of observers, to test the quality of light sources, and or to demonstrate disagreement caused by "pseudo," or false, color matches. There's a